In an architecture of computer science, a virtual machine (VM) refers to a special software, which can create an environment between a computer platform and a terminal user, and the terminal user operates software through the environment created by the VM software. Through the VM software, a user may simulate multiple VMs in one physical machine to speed up data processing.
In a cloud computing environment, there is large number of clusters consisted of multiple VMs, and the VMs in the cluster are redundant to each other. If the VMs redundant to each other are deployed in a same physical machine, the entire cluster may fail once the physical machine fails.